Object selection problem in 3D view
This is because there are really three selection states:


Deselected

No outline or origin shown:


Selected

Orange outline and orange origin:


Active

Yellow outline when also selected, yellow origin:

 

&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Active + Selected &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Active + Deselected


There is only one Active object. This object is the one which will be edited, if any changes are made in the properties region or edit mode etc.
In your screenshot you'll notice that the camera is still active, even though you deselected everything. To fix this,

The Active object is normally the last object clicked with  RMB. To set the active object without deselecting all other objects you can use &#8679; Shift RMB.